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$300 A4 Won't Start After Head replacements...Who Woulda Guessed?

As the title says, I got this car for $300 after the PO snapped the timing belt and had no idea what was wrong or how to fix it.
I pulled and replaced both heads, and put the motor back together as I did with my last B5 S4. I followed the Blauparts tutorial and the lock bar locked in after a few manual engine rotations.

I went to start it, and the below video shows what happened. I've been trying to start it for a day now, and have tried the following:

- Checking spark plug wiring is correct. It is
- Checking fuel pump fuse. It is OK. All fuses are OK
- Checking fuel rail for pressure. There is sufficient pressure and definitely fuel.
- Checking for Fault Codes in VCDS. There are none besides the one for removing the battery.

Compression sounds good (nice, even rhythm cranking at the beginning of the video).

Battery sounds very strong.

Make 1000% sure you have the plug wires installed in the correct locations/order.

Sounds to me like it may be firing the wrong cylinders due to being mechanically out-of-time (timing belt and/or chain) or having the plug wires mismatched.

You have some combustion, so I don't think it's a dead crank sensor. But (assuming the belt/chain timing and plug wires are all good), it could be a lousy crank sensor signal (ie: a crappy waveform). This will wreak havoc with the ECU's ability to find TDC and inject/spark at the right time. I'd say that's an outside case, but possible with a faulty sensor or incorrect sensor position.

Clever. I didn't look very hard apparently.
I'll swap them when I get home and post an update.

Also, this connector leads to a black 2-pin connector that is not attached to anything. This is right next to the power steering reservoir, under the plastic cover. I've searched high and low, but don't see where its supposed to go. Any ideas?IMG_0342[1].jpg

OK, switched the 4&5 spark plug wires, and it's definitely better than it was before, but it's still not running well.
It finally turned over, then I gave it some gas, and as soon as I let off the throttle, it died on it's own.

OK, I turned it over a few more times, and applied more throttle. It will idle on its own now. BUT it hesitated hard when throttle is applied, and then develops a rough idle for a bit.
Exhaust is pretty thick white smoke as well.

Well, if the thing hasn't run in a while. It may need run up to temp.
- How old is the gasoline?
- Have you done a throttle body adaptation?
- Do you have any engine codes set, now that the engine has run a bit? (Even if CEL is off)

The smoke could indicate some coolant entering one of the chambers, but I wouldn't get too worried about it yet.

- Gas is as old as the car has been sitting. I believe 6-8 months. I put 2 gallons of 87 in yesterday
- I have not done a TBB adaptation. Haven't even heard of it TBH
- I don't see any engine codes in VCDS going -> 01 Engine -> Fault Codes

I am going to give SeaFoam a try. Maybe the injectors are clogged? Maybe the fuel is bad?

- Adapt the Throttle Body
- Take it for a good romping
- And get some dang Premium Fuel in the tank. lol
- (Best would be to run through the junk that is in there as much as you can, then put in at least 5 gallons of the good stuff).

After said romping:
- check for codes
- take the spark plugs out and see how they look

I bought a 98 2.8 from someone for nothing a few years back and it wouldn't run on its own unless the throttle was constantly being pressed. Removed the throttle body and cleaned it good, did a throttle body adaptation via VAGCOM and it ran beautifully. Sold it for $4k a few weeks later :)